1. Field of the Invention
The present invention relates to a Bourdon tube pressure gauge used by mounting on a fluid pressure equipment or device such as pressure control valve.
2. Description of the Prior Art
As a Bourdon tube pressure gauge of this type, a pressure gauge is known, for example, as disclosed in Japanese Utility Model Publication 5-39471. In this pressure gauge, an internal device comprising a Bourdon tube and a converting mechanism for converting deformation of the Bourdon tube to a movement of a needle is accommodated in a case, and the rear surface of the case is covered with a back cover. A plurality of mounting screws penetrate through the case and the back cover, and the pressure gauge is fixed on a pressure control valve by these mounting screws.
In the pressure gauge as described above, however, the mounting screws are easily separated from the case and the back cover when the pressure gauge is not fixed on the pressure control valve. As a result, the mounting screws are often separated and dropped off and lost during transportation or mounting operation, and this results in inconvenience or trouble in mounting and handling operations.
Also, when the pressure gauge is fixed on the pressure control valve, the force to fasten the mounting screws is directly applied on the case, and the case may be damaged if it is made of a material such as synthetic resin.